Device for fixing holes by method of smelting,especially into building walls made of concrete,granite,sandstone or limestone,and method of producing the device



Aug. 12, 1969 ,5, aangzgs ET AL 3, ,223

DEVICE FOR FIXING HOLES BY METHOD OF SMELTING, ESPEGIAI'JLY INTO BUILDING WALLS MADE OF CONCRETE, GRANITE, SANDSTONE OR LIMESTONE, AND METHOD OF PRODUCING THE DEVICE Filed Aug. 2, 1967 2 Sheets-Shut 1 If //V \N\ rilrlllflll N W H \\m/i &/ L n l L \\\N\\\\\\ Aug. 12, 1969 2. s. BERCZES ETAL 3,

DEVICE FOR FIXING HOLES BY METHOD OF SMELTING, ESPECIALLY INTO BUILDING WALLS MADE OF CONCRETE, GRANITE, SANDSTONE OR LIMESTONE, AND METHOD OF PRODUCING THE DEVICE Filed Aug. 2, 1967 2 Sheets-Sheet 2 United States Patent 3,460,223 DEVICE FOR FIXING HOLES BY METHOD OF SMELTING, ESPECIALLY INTO BUILDING WALLS MADE OF CONCRETE, GRANITE, SAND- STONE GR LIMESTONE, AND METHOD OF PRODUCING THE DEVICE Zsolt Gyiirgy Brczes, 8 Sandacker 8052, and Attila Brces, 328 Birmensdorfersu'. 8055, both of Zurich, Switzerland Filed Aug. 2, 1967, Ser. No. 657,922 Int. Cl. 3321f 45/00; F23b 13/26 US. Cl. 29157 1 Claim ABSTRACT OF THE DISCLOSURE A method of forming a burner pipe for cutting holes in building walls made of concrete, granite, and similar materials is accomplished by inserting a bundle of fuse wires into the burner pipe so that a portion of the bundle of wires still projects from one end of the pipe and then spreading and bending the projecting ends of the wires outwardly from the axis of the pipe and finally inserting the projecting wires into the pipe so that they provide a self-locking engagement therewith.

Summary of the invention Until the present time the building trades have had to rely mainly on drilling machines for boring locating or hearing holes into walls of concrete, granite or limestone, and the like. The formation of such holes has been a time-consuming, irksome, noisy, dust raising, and vibration producing operation.

At the end of the last century, a method had been developed to produce holes in the walls of buildings constructed of concrete or stone by the use of heat. In this method a steel pipe was used, through which oxygen under high pressure was supplied and then ignited. The method was based on the recognition that by quick oxidation of a material-preferably iron-the combustion effected produced an extreme extremely high temperature.

However, in order to obtain the desired result, though only approximately, the pipe wall thickness had to be established in a precisely determined ratio to the quantity of the oxygen supplied. The greatest difliculty experienced in to practicing this method consisted on the one side in the precise regulation of the oxygen supply, and on the other side in a very high combustion velocity of the steel pipe.

At the beginning of this century, it had been proposed to fill the steel pipe employed for the described purpose with steel wires, attaining herewith:

(a) That a more equal distribution of the oxygen took place within the steel pipe, and henceforth a more equal combustion of the steel pipe,

(b) That a lesser length of combustion of the steel pipe was necessary with relation to the molten stone and concrete, since by filling the steel pipe with steel wires a considerably higher quantity of thermal energy could be gained, and

(c) That with the steel pipe filled with steel wires one could work much longer and that due to the regular combustion of the steel pipe considerably better results could be obtained.

Until the present the belief prevailed that the melting process was accomplished by the influence of high temperature on the stone and the concrete. Yet, careful examinations have shown that the accomplishment of the melting process requires still another highly essential part.

ice

It has indeed been proved that the molten steel of the steel pipe enters into a chemical compound with the silicon contents of the molten stone and concrete (iron oxid silicic acid). This compound has a much lower melting point than the stone or the concrete has on its own.

When applying the last described method with high heat development, two different reactions result in the stone and the concrete, namely:

(1) A smelting of the material to be treated, and

(2) A breaking or chipping of the material at the point of contact with the burner pipe, produced through a change of tension of the material.

In order to increase the temperature when executing the last described method, tests have been made by blowing aluminum powder through the steel pipe together with the oxygen. While a considerably better development of heat was obtained, the method proved to be uneconomical and, moreover, the small explosions which resulted were irritating because of the noise.

The recognition that base metals have a very high affinity for oxygen and therefore, they develop exothermic reactions which produce a much higher heat content than the exothermic reactions limited to the combustion of oxygen and steel led to tests in which base metals in powdered from together with iron powder in compound with oxygen were blown through the steel pipe. To carry out this method a complicated, expensive and rather bulky supply mechanism consisting of various tanks, mixing units and special connectors, etc. was needed. The method proved to be uneconomical, and it could be employed only to a limited extent.

In the United States a special method has been developed for forming holes into very hard ores (tacanites), in which method a mixture of petroleum and oxygen is employed. Unfortunately, this method has the disadvantage of requiring a large investment of machines and of using a quite considerable quantity of petroleum and oxygen.

In devices which use the above described steel pipe containing wires, it has proved necessary to secure the wires within the steel pipe against involuntary loosening and displacement. Until the present, the interior of the steel pipe has been equipped with a multitude of pins set at regular intervals, which exert a clamping effect on the inserted wires. This type of mounting for the wires in the steep pipe has, nevertheless, the considerable disadvantage, as experienced in practice, that the pins formed on the interior wall of the steel pipe create a resistance to the supply of oxygen, and a turbulent flow pattern is developed which causes irregular combustion of the inserted wires.

The object of the present invention is to overcome the above described disadvantages experienced previously in the attempts to use this method.

The invention refers to a method of constructing a device for forming holes by the method of smelting, especially in building walls made of concrete, granite, sandstone or limestone.

The inventive device distinguishes itself in that is consists of a steel pipe removably connectable to an oxygen feed pipe with a plurality of fuse wires arranged in a selflocking manner in the steel pipe.

The method of producing the inventive device consists in introducing the fuse wires in bundles into the burner or steel pipe so that they jut out for a certain length at the end at which they are introduced into the steel pipe, and then the individual wires jutting out of the steel pipe are splayed outwardly relative to the axis of the pipe so that when pushed into the steel pipe they are fixed there in a self-locking arrangement.

In the enclosed drawing two practical examples of the device according to the invention are represented, namely:

FIG. 1, a longitudinal section of a burner pipe, according to one embodiment of the invention, with the fuse wires partially introduced,

FIG. 2, a transverse section passing of the embodiment illustrated in FIG. 1,

FIG. 3, a longitudinal section of the burner pipe in FIG. 1 with the wires fully introduced, and

FIG. 4, a cross-section through burner pipe according to a second embodiment.

The device illustrated in FIGS. 1 to 3, consists of a cylindrical steel burner pipe a which serves to receive a bundle of fuse wires b, having a length such that when they are fully introduced into the operating position within the pipe they reach from the front and to the rear end of the burner pipe a. At its front end the burner pipe a a protective cap c, see FIG. 3, which is removable when the burner pipe is being used. At its rear end the burner pipe a has screw threads on its outside surface arranged to receive the corresponding internal thread of a connector sleeve d for joining the burner pipe a to an oxygen feed pipe, not shown on the drawing.

The method for producing the described device is accomplished as follows:

As shown in FIG. 1 a bundle of fuse wires b, disposed in parallel relationship with each other, are introduced into the burner pipe until their rear ends jut still out for a certain amount, e.g. 2 to 4 in., at the rear end of the burner pipe a, as shown in FIG. 1 of the drawing. Thereupon the parts of the fuse wires b, jutting out of the rear end of the burner pipe a, are splayed or bent upwardly as shown in FIG. 1 with the help of a convenient tool, and then in a further step of the method the splayed parts of the bundle of fuse wires are fully inserted into the burner pipe a. The splayed ends of the fuse wires act as a selflocking mounting support for the whole bundle in the burner pipe 0, until the wires b are entirely molten.

After the complete insertion of the bundle of fuse wires into the burner pipe a, the removable protective cap c and the connector sleeve D are added to the device (FIG. 3).

As shown in FIG. 2, there exists flow paths for the full length of the burner pipe, for unrestricted passage of the supplied oxygen, so that a uniform combustion of the fuse wires is attained when working with the described device.

While normal steel wire is suflicient for insertion into the burner pipe a when using the described device on building walls formed of concrete, sandstone or granite, a higher temperature is desirable when the device is used on basic or highly calcerous stone as well as certain types of concrete, in which case the fuse wires are composed more appropriately of an alloy of steel-silicon carbide. Practical tests have proved that in such cases an excellent economical effect is obtained when the fuse wires b have a silicon content of about 3% and a carbon content of about 1%.

Thorough investigations have indicated that an optimum result is obtained when the diameter of each fuse wire b inserted in the burner pipe a is in a determined ratio to the wall thickness of the burner pipe 0, for instance with a wire diameter of about 0.118 in. the wall thickness should be about 0.087 in.

Furthermore, testing has established that the total of the cross sectional areas of the fuse wires b inserted into the burner pipe a must be in a determined ratio to the internal diameter of the burner pipe a, and that a favorable void ratio is calculated in the manner of the following example:

Diameter of the fuse wire: 0.118 in.

Wall thickness of the burner pipe: 0.087 in.

Internal diameter of the burner pipe: 0.492 in.

Number of wires inserted into the burner pipe: 12 pieces Total cross sectional area of 12 fuse wires: 0.132 sq. in. Internal cross sectional area of the burner pipe section:

0.189 sq. in.

Volume of voids=0.l89 sq.

0.132 sq. in.

0.057 sq. in. 0.189 sq. in. 30%

For drilling the holes with the above described device, for instance into a concrete wall, the feed pipe of an oxygen bottle, not shown on the drawing, is joined to the connector sleeve d (FIG. 3), the protective cap 0 is removed from the burner pipe a, and a pressure regulating valve of the oxygen bottle, not shown on the drawing, is opened to such extent that the oxygen is supplied at a gauge pressure of about 5 kg./cm. through the burner pipe a. Ignition is attained at the front end of the burner pipe or by means of an auto-genous cutting torch or charcoal. Then the front end of the burner pipe a is brought into contact with the material into which a hole is to be formed, whereby the melting process between the front end of the burner pipe a and the front tips of the fuse wires b on one side and the material on the other side goes on until the hole has reached the desired depth.

The device according to the practical example as shown in FIG. 4 dilfers from the first described example inasmuch as the cross-sectional shape of the pipe (1 is chosen such that the fuse wires b form a compact bundle, whereby regular conduits or passageways for the oxygen are automatically obtained between the fuse wires b and the interior Wall of the pipe a.

As shown in FIG. 4, the twelve fuse wires b are combined in a bundle with a regular cross-section form. The burner pipe a has the cross-sectional shape of an equilateral triangle with rounded angles, and is adapted to the cross-sectional area of the 'bundle so that the fuse wires form a compact bundle and fill up, in almost completely (the free space between the bundle of wires and the interior wall of the pipe, oversized in the drawing, is only conditioned by the manufacturing process). In this arrangement almost equal cross-sections areas for the conduits c for the passage of the oxygen are obtained automatically between the wires b at the circumference of the bundle and the interior Wall of the pipe a, hence an equal fusing is obtained all-round for both the pipe and the fuse wires b when in use.

The last described device differs from the first described example with the round burner pipe only inasmuch as the pipe is flattened on three sides, however, when the same sizes are utilized (thickness of pipe wall, diameter of wires) the same results are achieved. In principle, the form of the cross-sectional areas of the burner pipe and of the bundle of wires can be varied to some degree, depending, of course, 011 the number of wires employed, whereby the best possible arrangement with regard to the most favorable utilisation of the burner pipe has to be established by experimentation.

The fuse wires can be used with an aluminium coat on their surfaces, by means of which an especially favorable elfect of heat is obtained.

The device embodied in the described examples has the advantage of being of a simple construction and, therefore, favorable in price, and furthermore that it is easy to haudle, allowing for more eflicient operation.

What is claimed is:

1. A method of making a burner pipe which contains a plurality of fuse wires and is connectible to an oxygen feed pipe for forming holes in building Walls and the like which are constructed of concrete, granite, sandstone, limestone, and similar materials, comprising the steps of arranging a bundle of the fuse wires in substantially parallel relationship; inserting the bundle of fuse wires into Void ratio:

relative to the axis of the pipe; and then inserting the 5 spread and bent ends of the bundle of wires into the burner pipe whereby due to their spread and outwardly bent configuration they become resiliently clamped by the interior wall of the pipe forming a self-locking engagement therewith.

References Cited UNITED STATES PATENTS 3,003,623 10/1961 Paul et a1 206-46 3,260,076 7/1966 Humberg 43199 FREDERICK KETTERER, Primary Examiner US. Cl. X.R. 

